Sandpapering machine



U. G. NORMAN.

SANDPAPERING MACHINE.

APPLICATION FILED APR. II. 1918. RENEwED OCT. 22. I92I.

1,406,275, PeIenIeII FeIe.14,1922.

2 SHEETS-SHEET l.

C. G. NORMAN.

SANDPAPERING MACHINE. APPLICANON FILED APR.11.1918. RENEwED ocT.22.192|.

l ,406,275 Patented Feb. 14, 1922.

2 SHEETS-SHEET 2.

cam. e. Nonnen', or onroaeo, ILLINOIS. l

smrnranmo mennen Speeioation of Letters Patent.

Patented Feb. 14, 1922.

Application led April 11,1918, Serial No. 227,896.l Renewed October 22,192.1. vSerial No. 509,529.

To all whom it ma/y concern.'

Be it known that I, CARL G. NORMAN a citizen of the United States,residin at C icago, in the countyiof' Cook and tate of Illinois, haveinvented a certain new and. useful Improvement in Sandpapering Machines,of which the following is a full, clear, concise, and exact description,reference being had to the accompanying drawin, forminga part of thisspecification.'-

y invention relates to sand lpaperlng machines, and has to do with theprovision of means for resiliently carryin the abra. sive material sothat an even polish of iloors or other surfaces to be finished may besecured.

With the use of the devices of the prior art, which were ordinarilyprovided wlth a drum having sand paper dlsposedover the outside of thedrum but having no resilient means between the sand paper and the drum,a smooth finish could -be obtained only'by an experienced operator forthe reason that during the rotation of the drum contact with the floorvwas made only alongv Ia single line. Unless movement of the rotatingdrum across the floor was maintained constantly, grooves resulted due tothe rotation of the drum in a sin le position. Frequently padding, suchas elt, would be placed between the sand paper and the drum but after ashort time the padding would' pack with the result that its ,usefulnesswouldbe-destroyed.

Another objection to these devices is thel constant vibration of theentire machine asthe rotating drum engages the floor. 4

Broadly, my invention comprises a drum, or va pair of drums, having aAplurality of leaf springs secured to the outer side, each of .thespringinembers havin pointing away from the direction of the rotation ofthe drum so that centrifugal force will cause the free ends of thespring members to move outwardly and as the springs engage the Hoor orsurfaces to be polished a contacting surface of about three or fourinches is obtained when' a drum of about twelve inches 1n diameterisused. I have found that substantially the same 'operation is eected asis obtainedby hand sand papering, and this is manifested by the char.-acter of theshavings which are long and shred-like as .distinguishedfrom the dust which ordinarily resultsv from the use of sand paperingmachines in use heretofore.

My invention will be understood more -a pair of drums 19 and 20 whichare simia free end clearly by reference to the accompanying drawings, inwhich- Figure 1 is a side view of my improved sand papering machine;

Fi ure 2 's a horizontal sectional view showing parts of the mechanismin section and yparts in elevation;

Figure 3 is a perspective view of the drums sup orting the springs andabrasive material. his view also shows the fan mechanism for drawing theshavi from within the housing and directing t e same through a chuteleading to a receiving rece tacle;

igu're 4 is a perspective view of one of the leaf springs used forsupporting 'the abrasive material; and

Figure 5 is a detail view showing the method of adjusting the machine.

SimilarV characters of reference refer to similar parts throughout theseveral views.

.fis seen in Figure 1, the machine comprises' a housing 1Q mounted on apair of wheels11-11 and adjustable rollers 12-12 by means 'of which theabrading elements may be adjusted relative to the surface to befinished. A motor 13 is mounted on the `housing and. connected to ashaft 14 by means of avchain 15 passing over a gear 16 keyed orotherwise secured to the shaft.

The shaft 14, preferably, ismounted in ball bearings carried by thehousingto secure Aeasy and noiseless operation. The machine is movedover the floor by means of a handle l? on which can be located a switch18 for controlling the electric current necessary for operating themotor 13. Within the housing 10 and mounted upon the shaft 14 is lar inconstruction. These drums are secured to the vshaft 14 by means of setscrews 21 passingA through the hubs of the drums and engaging the shaft14. Each of the drums 19. and has a flan ed portion 22 and 2.3 providedwith an annu ar groove 24and 25 into which extend the edges of a ring 26supported by arms 27 connecting the inner side of the rin 26 to the hub29 -disposed around the sha t 14. Ball bearings 31 and 32 are providedin each'end of the hub 29 through which the shaft 14 passes. The

ring 26 is stationary and is provided with an opening 34 through whichpasses the chute of sheet metal 35 communicating with 110 a dust box'36.' h

. Although it would be possiblealto employi i dispose portions of thecanvas one rotatable drum I have found it desirable to employ two forthe reason that irregularities in the vfloor level are accommodated moresatisfactorily. The chief object of the ring 26 is to provide a meansfor effecting a. single chamber within the drum so that the shavings canbe controlled.

Within the drums 19 and 2O I have arranged fan members 38 and 39arranged to cause a circulation of air within the housing of the machinewhereby the shavings and dust resulting from a. Eolishing operation aredirected through t e chute and 'into the box 36.

The drums 19 and 20 are each provided with a plurality offfixtures 40secured to the outside of the drums by means of the screws 41. Thescrews 41 extend upwardly beyond the outer` sideof the fixtures, theobject of which will appear presently. fixtures 40 are eaclr bentupwardly at 42 to receive one end of, an arcuate spring membe'r 43secured to the portion 42 by means of bolts. The end portion of the spis bent upon itself, as illustrated at 44, to provide a resilientabutment for the spring 43 in o eration. A padding of felt 46 is overeach spring 43 and held in place by a clamping member 47 which isprovided with a pair of keyholev slots 49- 49, the enlarged opening 50of which is arranged to be slipped over theheads of the screws 41. i

The abrasive means consists of a piece of canvas orother heavy cloth 52on one side of which is glued@ sheet of sand paper or other similarmaterial 53 terminati on substantially asi lustrated. In practice it hasbeen found that if sand paper alone is used the vibration y at or nearthe free end of tlicfspring-mem-A of the of t e same.

rs is such as to cause crackin paper and eventual breakin t will be seenthat the sand paper termif nates at about the point of greatestvibration and the strength and flexibilit of the canvas lpermits thismovement wit out in- Jury. contemplate the use of a` piece of canvashavin sand a er lued to one face for each of t 'pp g e spring members 43and to assemble the same the ends of the canvas are brought adjacent thefixtures 40, after which the clampin members 47 are slipped e screws 41,are brought down against the canvas and are retained in position by theinwar movement of the clamping` members.

In use the drums are always rotated in the direction indicated by thearrow, which,

inw this case, is a clockwise direction, but it will be understood thatthe direction of rotation is determined by the .free ends of the sprinmembers 43. The machine may be movedg either forwardly or rearwardl overthe il'oor or other surface to be nishe The ring 43A ends and as thesprinlg members rotate the centrifugal force wi tend to cause theirmovenient outwardly and as they are brought into engagement with thefloor a broad con# r this,

by the movement of their supporting shaft by means of adjusting-deviceson each side of the housing. As shown in Figure 5, each of theseadjusting devices may consist of' a set screw 55 operating' in a bracket56. The set screws 55 have an enlarged o` rating in an opening 58 1n t55e By the operation of the set the desired sition with respect to. thefloor can be o ained. I

Although I have described my present invention in connection with amachine for sand papering floors I am` aware that with slightmodifications the same can beada ted for ,polishing and sandin other suraces e support and can be used in finis ing in a large. lvariety ofmethods.

ortion 57 abrasive material on its face and secured to said rotatablemeans, and clamping means arranged to hold: the yiexible material inp1ace..

2. In combination, means carried therebl a spring member se cured tosaid rotatable means, and hav a end portion thereof pointing oppositethe direction of rotation, having abrasive material on its face and seasupport, rotatable flexible material cured to said rotatable means, andclam ing means to hold the flexible material in p ace. 3. An abradi'ngelement comprising a shaft, a Pulley mounted on said shaft,-a pluralityo arcuate lea'fs ring members each having one end secure to said pulleyand the ot er end free from said ulley, the free of said spring memberscurved on the vinner sides ofl said sprin members to form bu' d ersbetween sai s ring members ansdpulleypieces of ilexion t b e materialdispo e free ends of said spr' members and said pulley for limitingHinge outward movement of said spring members, and abrading materialseing reversely (ured to the. outer sides of said spring memers.

4. An abrading element comprising a shaft, a pulley mounted on saidshaft, a plurality of each having one end secured to said pulleyI andthe other end free from said pulley, pieces' of flexible materialdisposed on the free ends of said spring members and said pulley forlimiting-'the outward movementof said spring members, andabradingmaterial secured to the outer sides of said spring members.

5. An abrading element comprising a shaft, a pulley mounted onsaidShaft, a plurality of arcuate leaf springA members each having one endsecured to-said pulley and the other end free from l:said pulley,flexible material for limiting the outward movement of said springmembers, and

abrading material disposed on the'iouter sidesof said spring members.

. 6. ln combination, a support,an abrading element mounted forrotationiin said support, said abrading element comprising a drum, aflexible element secured lat intervals tothe periphery of said drum,abrasive material carried on the face'of said! flexible element, arcuateleaf spring members secured to the periphery of said drum and arrangedto urge the flexible element away from the.

periphery of said drum to engage a surface to be abraded, said flexibleelement limiting he outward movement of said spring memers.

7. An abrading element comprising a pulley, a flexible element looselyembracing the periphery of saidpulley, means for clamping said flexibleelement at intervals to the periphery of said pulley, abrasive materialcarried on the outer face of said flexible element, spring meansdisposed at points intermediate said clamping means and secured to theperiphery of said pulley and arranged to urge lthe flexiblerelement awafrom the periphery of said drum to e ect a resilient abrasive surfacesubstantially as and for the purpose described. y

8. An abrading element comprising a pulley, a flexible element looselyembracing the arcuate leaf spring members.

means for clampperiphery of said pulley,

the

ing said flexible clement at intervals to periphery of said pulley,prising a bar provided with keyhole slots, abrasive material carried onthe outer face of said exible element, spring means disposed at pointsintermediate said clamping means and secured to the periphery of saidpulley and arranged to urge the flexible element away from the peripheryofA said drum to effect a resilient abrasive surface substantially asand for the purpose described.

V9. An abrading element comprising a pul.

a flexible element loosely embracing the A means for clampat intervalstoI the resilient abrasive surface, substantially as and for the purposedescribed.

'10. An abrading element comprising a pulley, the periphery of saidpulley, means 'for clamping said flexible element at intervals to theperiphery of said pulley, said means comprising a bar provided 'withkeyhole slots, abrasive material carried on the outer face of saidflexible element, a plurality of arcuate leaf spring members each havingone end secured to said pulley and the other end free from said pulley,the free ends of said spring members being reversely curved on the innersides of said spring members to form buers between said spring membersand said pulley, to effect a resilient abrasive surface, substantiallyas and for the purpose described.

ln witness whereof, I hereunto subscribe my name this 8th day of April,A. D. 1918. CARL Gr. NORMAN.

Witnesses: Y

ALBIN C. AHLBERG, ANDREW WINTERCORN.

said means com a flexible element loosely embracing v abrasive material

